Update `.latexmkrc'

.latexmkrc

@@ -1,6 +1,7 @@
 # Latexmk configuration file.
-
-# Set environment variables.
+#
+#   WARNING: Only works with version 4.59 or higher of latexmk.
+#
 
 # Set timezone.
 $ENV{'TZ'}='Asia/Shanghai';
@@ -10,10 +11,16 @@ ensure_path( 'TEXINPUTS', './texmf//' );
 
 # Use lualatex with latexmk.
 # $pdf_mode = 4;
+
 # Use xelatex with latexmk.
 $pdf_mode = 5;
+
+# Disable postscript and dvi output.
 $postscript_mode = $dvi_mode = 0;
 
+# Add common patterns for tex engines.
+set_tex_cmds( '-synctex=1 %O %S' );
+
 # Always try to embed fonts, ignoring licensing flags, etc.
 $xdvipdfmx = 'xdvipdfmx -E -o %D %O %S';